Excavating-machine.



C. B. KING, G. HOLMES, B. JACOBY a HNE. ROUSH.

EXGAVATING MACHINE.

APPLIOATION FILED MAYSl, 1911.

C. B. KING, G. HOLMES, B. JACOBY & H. E. ROUSH. EXGAVATING MACHINE.

APPLIOATION FILED MAY 31, 1911.

Patented Feb. 9, 1915.

4 SHEETS-SHEET 2.

@nvm/116015 C. B. KING, G. HOLMES, B. JAGOBY & H. E. ROUSH. 4EXGAVATING MACHINE.

APPLICATION FILED MAY s1, 1911.

- Patented-Feb. 9, 1915.

4 SHEETS*SHBET 3.

G. B. KING, G. HOLMES, B. JACOBY L H. E. ROUSH. EXCAVATING MACHINE.

APPLIGATION FILED 11111531.1911.

Lmlm. Patented Feb.9,1915.

4 SHEETS-SHEET 4.

' and State of trib l `111 CHARLES IB. KING, MARION, OHIO, GRANT HOLMES, OF DAN'VILLE, ILLINOIS, AND BENJAMIN JACOBY AND HEB-BERT E. ROUSI'I, OF MARION, OHIO, ASSIGNORS TO THE MARION STEAM SHOVEL COMPANY, OF

dllljl. Specification of T0 all whom t may concern: l

Bc it lknown that we, CHARLES B. KING, residing at Marion, in the county of Marion Iand State of Ohio, GRANT HOLMES, residing at Danville in the county of Vermilion llinois, and BENJAMIN JA- coy and HERBERT E. RoUsH, both residing atMarion aforesaid, citizens of the United States, have invented certain new and useful Improvements in Excavating-Machines, of which the following is a specication, reference being had therein to the accompanying drawings. V,

This invention relates to excavating machines, and more particularly to excavating machines of the dipper type and is designed especially for stripplng coal, that is, removing` the surface layer of earth and rock covering coal veins which lie close to thetop of thel ground.

The object of the invention is to providean'ex-cavating machine of this character which can be operated to make excavations at any' point about a circle and which will automatically accommodate itself to the unevenness of the tracks without imposing any severe strain upon the frame or mechanism. i

To this end it is a further object of the inventionto provide such a machine supported by four trucks, two of which are vertically. adjustable; to provide means for equalizing the movement of said adjustable trucks; and also to provide means for controlling the several parts of the mechanism.

'In the accompanying drawings,'Figure 1 is a top, plan view of an excavating machine embodying oury invention with a portion of the frame broken away; Fig. Slis a 'front elevation of the same; Fig. 3 isa longitudinal, sectional view, taken on the line a;

l of Fig.y l. and looking in the direction of the arrows; Figs is a plan View ofthe rear portion of the supporting frame showing the. support-s for the adjustable trucksan'd the connections' between the same; and Fig.

` 5 is a verticahsectional view, 'taken on the line y-y LofFig. 4. 'with the'central portion'of' the vframe brokenY away. Y

lnthese' drawings We have illustrated one.` en'lbodirnentlIl of invention and' `have shown ,the/s, es .applied `to an excavating MARION, OHIO, A. CORPORATION OF OHIO.

EXCAvATING-MACHINE.

Leterratent. Paramedische, iaia.

Application led May 81, 1911. Serial No. 630,281.

machine of the boom and dipper type comprising a platform upon which is rotatably mounted a frame carrying thel boom, the power plant and operating mechanism for the boom and dipper. The platform is preferably rectangular in shape and is supported at eachcorner by a four wheel truck, which trucks travel on tracks arranged along 'theopposite sides of the machine. Two of these trucks are vertically adjustable, the adjustment being preferably automatic to enable the trucks to accommodate themselves to irregularities in the tracks and thus maintain the several parts of the frame in their proper alinement and avoid imposing anyA severe strain upon the platform or frame or the 'mechanism carried thereby. 'The :adjustable trucks are connected one with the 'other in such a manner as to equalize their movement. V f As here shown the lmachine'comprises a supporting platform 1 which is rectangular in shape and substantially square. platform is provided at each of its four corners withV trucks 2 and 3. The trucks 2, which are'located at the forward end of the platform, 'are'vertically adjustable and the trucks 3,' whichare' located at the rear of the platform', arel propelling trucks to move the machine as a whole over the tracks. The trucks themselves may be ofany suitable character and the four trucks are substantially the same in construction, each comprising four double flanged wheels 4: mounted in 'pairs-on axles 5, which axles are journaled-in bearings carried by a truck frame 6.

Each truck 'frame ispreferably formed of a connected .with `the' platform by ball and ...socketfjointa and, to this end, each truck frame'fis provided'near' its center with a cup or socket- Qradapted to' receive the rounded f lower fend of a standard secured to the platform'SLiL In' the ease of the rear trucks these standards arerigidly secured to the platforinyas indicated at'l0-, while inthe case of the forward or adjustable trucks the standards are adjustably connected t o the platform and constitute pistons, as indicated y at 11. Each piston 11 is mounted in a cylcasting and cylinder are provided with interlocking flanges lil and 15, respectively, arranged to resist any tendency on the part ofthe cylinder 12 to move upward but to permit the removal of the cylinder. The cylinders may be filled with any suitable fluid, such, for example, as water, and are interconnected in such a manner as to equalize the'movement of the pistons 11. This connection preferably comprises a pipe 16 extending transversely to the platform 1 and connected at its opposite ends to the upper portions of the respective cylinders 12. The

Ipipe and cylinders having been filled .with

fluid any upward movement of one piston must necessarily displace a quantity of the fluid which will flow into the other cylinder and cause, or compensate for, a corresponding downward movement of said other piston. The pipe 16 is provided with a cut-oil" valve 17 by means of which the communication between the two cylinders can be interrupted. When this valve is closed there is no means of escape for lthe fluid from the cylinder and where a non-eompressible fluid is used, the piston will be effectually locked against upward movement and but a very slight downward movement will be permitted, as such movementwould vcreate a vacuum within the cylinder. While the valve 17 will serve to lock the adjustable or floating trucks against vertical movement it is sometimes desirable, where the machine is being operated in one position for a considerable period of time, to have a positive lock which will not be affected by leakage or any other cause, and to this end, the lower portion f each piston 11 is slightly reduced in diameter and screw-threaded, as indicated at 18, and a nut 19 is mounted on the screwthreaded portion o fthe piston. By screwing this nut against the lower end of the correspending cylinder the piston will be locked against upward movement. Bv reducing the diameter of that portion of the piston in which the thread is formed the threadl is preventedfrom coming in contact with the bore of the cylinder when the threaded portion of the piston enters the latter. The construction of the piston and the cylinder is such as to effectually prevent the escape of the fluid about the lower end of the piston. As here shown each cylinder 12 is provided with a usual packing ring 20 and is further provided with a second packing ring -21 spaced a short distance below the packing ring 20. A groove 22 is formed in the inner face of each cylinder between the packing rings 2O and 2,1. These grooves are connected by pipes 23 and 24, respectively, with a receptacle 25. Any fluid which 'may work past the first packing ring, 20,

passing out of the lower end of the cylinder.

The. receptacle 25 has mounted therein a suitable pump 26 and is connected by means of a pipe 27 with the pipe 16 connecting the upper ends of the cylinders. By the operation of this pump the cylinders can be readily .recharged with the fluid and the desired quantity of fluid maintained therein. ly the use of the floating trucks and the equalizing device therefor the trucks and the platform will readily accommodate themselves to any unevenness in the tracks, and, by providing two floating trucks and two rigid trucks, we secure all the adjustability and flexibility of a three point suspension and, at the same time, retain all the rigidity of a four point suspension.

Rotatably supported upon the platform 1 isv a frame 28 upon which is supported a boom 29, the operating mechanism therefor and the power plant, this latter being preferably supported on a rearward eXtension of the frame, as indicated at 30. The frame 28 is connected to the platform 1 by and rotates about a central shaft or pin 31. An annular series of flanged rollers 32, connected one to the other by bands 33, are mounted between tracks 3-1 and 35 carried by the platform and frame, respectively. The hollow shaft or pin 31 is here shown as mounted in a casting 36 rigidly secured in the center of the platform 1 and is held against rotary movement therein by a ke)- 37, the key being of less length than the keyway to permit of a slight vertical movementon the part of the shaft. as hereinafter described. The frame 28 has secured thereto and preferably depending therefrom a casting 38 in which is formed a bearing for the upper portion of the shaft 31. Means are also provided for maintaining the frame substantially parallel with the platform and preventing the same from tipping. This is,

accomplished in the present instance by providing the upper portion of the shaft 3l with a art, such as an annular flange 39, arrange to engage the upper edge of the bearin 38 and by mounting on the lower end o the shaft 31 a screw-threaded nut 40. By tightening this nut the bearing 38 and the frame to which said bearing is rigidly secured can be drawn down and held firmly in their proper positions relatively to the platform. When the shafts have been drawn down in this manner the frame maaien will be prevented from.- tipping and throw'- ing the parts out of alinement,'and moreover, the whole construction of the machine f will be rendered' rigid andl theentire 'weight s of the platform, the frameand. the mecha.-

nism mounted thereon will lbe utilized to counter-balance the boom andthe load thereon, the platform pivotingl about the 'axis of the trucks ait the forward end thereof.

The propelling trucks at the-rear ofthe platform l are driven/from the engine car ried by the rotating frame28. vTo this end the inner wheels `of each truck 3 are pro.- r vided with-ftoothed anges orv gears 41` whlch mesh with and are driven-.by pinions 42 carried by shafts 43 mountedl in transverse bearings 44 carried by the respective trucks Y and 'preferably formed integral therewith. As here shown `each truck .is

provided with fan opening extending through substantially the full width thereof and having a bearing at each end to receive y the shaft 43,' this long bearing `serving to prevent the pinion from becoming displaced or out of alinementwith wear. The pinions 4:2- ar'e connected by of universal joints 45 with the outer" ends of floating shaft sections 4;6, thevinner 'ends of which are connected by other universal joints f7 with a shaft Section 48 journaled in fixed bearings `L9 carried by .the'platform 1. Rig- 58. The gear meshes with a correspolml-.V ing gear 5'.) loosely mounted on a shaftG()` which is provided at one end with a gear G1 meshing with a pinion 62 keyed to the shaft 63 of the hoisting engine 64. A second miter gear 65 is also loosely mounted on the shaft 60 and meshes with a corresponding lgear 66 mounted on a shaft G7 having at its other end a worm 68 supported in engagement with a worm wheel .69 on the drum 70.4

Each of the miter gears 59 and 65 onthe shaft 6() 1s provided on its inner face with a 'clutch member adapted to be engaged by the adjacent endr 'of' a clutch member 71v slidably mountedon the shaft (50 and con-y trolled inthe usual manner b v a: yoke 72, thus enabling both the propelling mechanism and the boom hoistingl mechanism to be controlled by a single lever.

The propelling shaft 56 is preferablyhol#y low to receive a water pipe 73 which 1s c0n.

nected at its upper end with the injector for the boiler and at its lower end with-the pinion is employed for this .here shown an annular rack 14 is .rigidly 1 'of the excavating mechanism.

water` supply. ln this manner wat-er .can be" ltaken on'without'interrupting-the operation g The frame 28 may be rotated by any lsuit- I Y able mechanism, but preferably a rack and urpose. As

Secured to the v platform 1f -con'centrically' with the shaft31.` A pinion 7 5,l carried' by a yshaft 76 rotatably mounted onv the frame 28,

meshes with the` rack 74, and, the rack being fixed, travelsalong the same, thereby causingthe frame'28to rotate. The-shaft 1 f 7 6 is preferably mounted in bearing brackets i 77 carried by the frame 28 and'has secured'v thereto a gear 78 which meshes with a pinion 79 mounted ona short shaft 80, lto .the upper end of which is secured a miter .gear 81l meshing with a corresponding gear -82 on vthe shaft 83 of the swinging engine-84. I

` Theoperation ofthe' mechanism as a.

whole will be readily understood from thel foregoingv description of the several `parts thereof and it will be apparent that we have' provided a shovelof Athis character which is mounted onv a plurality of trucks, a part of. which are floating trucks and will auto- `matically accommodate themselves to any .irregularities in the track, and, that by combinng the two floatingvtrucks with the two fixed trucks, we secureall the flexibility and adjustability of the three point suspension while retaining the rigidity of the four point suspension.- It will also be noted that wehave provided means whereby both trucksmay be moved in the same direction,

either toward or away from the platform, Y

to vary the, distance between the platform and the supporting surface, thus enabling the platform to be maintained substantially level when the machine is standing on a sharp incline.

quantity of fluid: into the lcylinders or by withdrawing fluid from the cylinders lnto This result is, in the present. instance, accomplished by forcing a greater the receptacl'efwhich isl provided to receive the same, thusjcau'sin 'the pistons to work at a `greater orlesseristance from the ends of their cylinders ,and consequently lengthening orv shortening the connections between the trucks andv the platform.l ln this connection it may alsol` be noted that 1t 1s not necessary to the-operation of the device, as

above described, that the *two normally fixed f Atrucks', should be incapablev of adjustment.

It is quite vvpossible to duplicate the adjust able trucks, which are here shown at the front endof the machine, at the rear end of the' machine, andl lby locking one set of trucks against 4movement the operation' above described would be had. Further, it

"will be apparent thatwith this construction itispossiblejto rotate the mainframe and to operate the excavating mechanism at -any'lpoint of the "circle described about the center of the rotating frame; further, that 'the frame is so connected to the platform that these parts are maintained at all times in substantially parallel positions and the frame is prevented from tllting and throwing any part of the mechanism out of alinement; and further, by connecting the frame rmly to the platform the whole weight of the platform, frame and the mechanism carried thereby is used to counterbalance the boom and the weight thereon. Further, it

will be' apparent that we khave provided means whereby the machine as a whole may be propelled through the truck wheels, this propellingmechamsm being actuated from the hoisting engines.

While we have herein shown and described one specific embodiment of our invention it will be understood that this embodiment is chosen for the purpose of illustration only and that we do not wish to be limited to the details of construction shown and described, for obvious modifications will occur to one skilled in the art. For example, it will be understood that the term truck is herein employed as meaning any member or device for movably supporting the different parts of a platform and is not to be limited to the fourl wheel trucks shown and described.

Having thus fully described our invention, what we claim as new and desire to secure by Letters Patent, is

, l.- In an excavating machine, the combination, with a supporting platform to carry the excavating devices, of a plurality of trucks tosupport said platform, two of .said trucks being connected with said platform on opposite sides of the center thereof and being capable of vertical movement relatively oneto the other and to said platform, a connection -between said vertically movable trucks to cause both of them to move relatively to said platform when one of them encounters an irregularity in the supporting surface, 4and means to prevent said trucks from moving relatively to said platform and to cause them to forma rigid support for said platform.

2.V In an excavating machine, the combination, with a supporting platform to carry the excavating devices, of a plurality of trucks to support saidplatform, two of said trucks being connected with said platform on opposite sides of the center thereof and being capable of verticaly movement relatively one to the other and to said platform, an equalizing connection between trucks to cause them to move simultaneously in opposite directions independently of said platform to adjust them to irregularities in the supporting surface, and means to lock said trucks in their adjusted positions. l f

3. In an excavating machine, the combisaid nation, with a su porting platform to carry the excavating evices, of a plurality of trucks to support said latform, two of said trucks being connected) with said platform on opposite sides of the center thereof and being capable of vertical movement relatively one to the other and to said platform, fluid controlled devices connected respectively with said vertically movable trucks, a connection between said fluid-controlled devices, whereby the vertical movement of either of said trucks will actuate said fluidcontrolled devices to cause the other truck to move in a direction opposite to the direction of movement of the first-mentioned truck to cause said trucks to adjust themselves to irregularities in the supporting surface, and means to lock said trucks in their adjusted positions.

pistons, whereby said trucks are capable of vertical movement relatively to said cylinders and said platform, saidA cylinders containing a non-compressible fluid, and means for connecting said cylinders one with the other to permit the fluid to flow from one cylinder to the other when either of said pistons moves vertically relatively to its cylinder.

5. In an excavating machine, the combination, with a supporting platform to .carry the excavating devices, of a pair of trucks arranged at one end of said platform on opposite sides of the center thereof and held against vertical movement relatively to said platform, two cylinders secured to the opposite end of said platform on opposite sides of the center thereof, pistons mounted in the respective cylinders, trucks arranged beneath said cylinders and connected with said pistons, whereby said trucks are capable of vertical movement relatively to said cylinders and said platform, said cylinders containing a non-compressible fluid, means for connecting said cylinders one with the other to permit the fluid to flow from one cylinder to the other when either of said pistons moves vertically relatively to its cylinder, and means to lock said pistons against vertical movement relatively to said platform.

6. In an excavating machine, the combination, with a'supporting platform to carry the excavating devices, of a pair of trucks arranged at one end of said platform on opposite sides of the center thereof and held aainst vertical movement'relaely toi ea'id patforim two-cylinders secured tothe'opposite end of said platform on opposite sides of thecenter thereof, .pistons' mounted the respective cylinders, trucks an ed beneath said cylinders and connected with 'said pistons, whereby said trucks are' capable'of l `vertical'movement relatively* tofsaid cylinders and said platform, said cylinderscontaining a` non-compressible fluid, means for connecting said cylinders one with' the other to permit the Huid to' flow from' onecylinder to the other when either of said pistons movesA vertically relatively to its cylinder,

andmeans to interrupt said connection to prevent the movement of said cylinders relatively one to the other and to said platform, thereby retaining the same in adjusted positions.

7. In an excavating machine, the .combiand connected with the pistons of'said cylin-v ders, and means for connectin said' cylinders one with the other to permit said 'trucks to rise and fall to adjust themselves to irregularities in the supporting surface.

8. ln an excavating machine, the 'comloic' nation, with a supporting platform tocarry the excavating devices, of a plurality of trucks to 'support said platform, cylinders secured to said platform near oneI end thereof and on opposite sides of the center thereof, said cylinders containing a noncompressible fluid, pistons mounted inl said cylinders, two of said supporting trucks being arranged beneath the respectivecylinders and connected with the pistons of said cylinders, means for connecting said cylinders one with the other to permit said trucks to rise and fall to adjust themselves to irregularities in the supporting surface, and means to lock said pistons against movement to retain. said movable trucks in their 4adjusted positions.-

9. In an excavating machine, the combination', with a supportingplatform .to carry the excavating devices, of a plurality of trucks to support said platform, cylinders secured to said platform near one end thereof and on opposite sides of the center thereof, said cylinders containing a noncompressilzile` fluid, pistonsmounted inpsaid cylinders, two of said supporting trucks being arranged beneath the respective cylin- .ders and connected with the pistons of said cylinders, means for connecting said cylinders one with the other to permit said trucks l fie' rise am rail te' ladjust'. t'limslws t@ if' regularities in the supporting surface, and

.means to .interrupt said connection -to retain said movable trucks' in their adjusted positions.

10." lhifan excavating machine, the combi-l nation, with a: supporting platform to carry I thel excavating devices, of a plurality of trucks to supportsaid platform, cylinders secured', to said platform vnear one end thereof` and on lopposite sides ofthe center thereof, said .cylinders-containing a nonconripres'siblel Huid, pistons mounted in said cylinders, two of said supporting trucks benig arranged lbei'ieath the respective cylinders and pivotally connected with the pistons of said cylinders, and means for connecting said cylinders one with the other to permit said trucks to rise' and fall to adjust thei'n'selvesv to `irregularities in the supporting surface.

'11. In an excavating machine, the com- .bina'tion with a supporting platform'to vcarryitli'e excavating devices, of a plurality of trucks to support said platform, cylinders secured' to said platform near one endv thereof and on opposite sides of the center thereof, said cylinders" containing a noncompressible Huid, pistons mounted in `said cylinders, two of saidsupporting trucks benig Varrar'i'ged beneath the respective cylinders, a universal pivotal connection between eac'hfof said trucks and its iston, and means for connecting said cylin ers onevwith the other to permitsaid trucks to rise and fall to adjust themselves to irregularities in the supporting surface.

12. lfn'anY excavating machine of the char`v acter described', thev combination, with a platf'oi'mto carry the excavating devices, of a pair of supporting trucks independently connected with said platform near one end thereof and on opposite sidesof the center thereof, said trucks being capable of vertical movement relatively toy said platform .and to each other, and interconnected fluidcontrolled devices connected with the re'- s'pective' trucks to cause them to move simultaneously in opposite directions and to adjust themselves to irregularities in the supporting surface.

13. In-an excavating machine of the character described, the combination, with a platform to carry the excavating devices, of a pair. of supporting trucks connected with said platform near one end thereof and on opposite vsides of the center thereof, said trucks being capable of vertical movement relatively to said platform and to each other, interconnected fluid-controlled devices connected with the respective trucks tofcause them to move simultaneously in opposite directions and to adjust themselves to irregularities'in the supporting surface, and means to' interrupt said connection between said uid-controlled'devi'ces toretain said trucks in their adjusted positions.

14. In an excavating machine, a platform to lsupport the excavating devices, independently supporting trucks arranged near the respective corners of said platform, the trucks at one end of said platform being vertically iiovable relatively one to the other and to said4 platform, interconnected iuidcontrolled devices interposed between the respective supporting trucks and s aid platform to cause said trucks to move in opposite directions to adjust themselves to irregularities in the supporting surface, the trucks at the opposite end of said platform being fixed against vertical movement relatively to said platform, power mechanism supported on said platform, and an operative connection between said power mechanism and said fixed trucks to cause the latter to propel the machine.

15. In a machine of the class described, a platform, a lurality of supporting vtrucks or sai-d plat orm, two of said trucks being vertically adjustable relatively tov said platform and to each other, fluid cylinders supported adjacent to said adjustable trucks, pistons connected with said trucks and extending into the respective cylinders, a connection between said cylinders, and a locking device carried byeach piston to lock said trucksl in adjusted positions.

16. In a machine of the class described, a platform, having a vertical opening therein, said opening being provided with an inwardly extending projection, a cylinder mounted in said opening and having an outwardly extending projection arranged to engage the first-mentioned projection, a piston mounted in said cylinder, and a truck connected with said piston.

17. In a machine of the class described, a platform, a substantially vertical cylinder carried by said platform and having `an annular groove in the inner surface thereof, a packing ring arranged above said groove, a piston mounted in said cylinder and having its inner end extending normally above said packing ring, a truck connected to said piston, a fluid receptacle, and a connection between said fluid receptacle-'and said annular groove.

18. In an excavating machine, a platform, a plurality of supporting trucks for said platform, two of said trucks being vertically adjustable relativelyto said platform and to each other, Huid cylinders carried by said platform Aadjacent to said adjustable trucks and having 'their' lower ends open, pistons mounted in said cylinders, connected with the respective trucks and having those parts arranged near the lower ends of said cylinders provided with screw-threads, and nuts mounted on the screw-threaded portions of said pistons and adapted to engage the lowerv ends of'said cylinders to lock said'pistons against upward movement with reltion to said c linders.

19; n an excavatin machine, the comblnation, with a platorm to support the excavating devices, of a plurality of trucks for supporting said platform, two fluidcontaining cylinders secured to said platform near one end thereof and on opposite sides of the center thereof, pistons mounted in said cylinders, two of said trucks being connected respectively with said pistons, a connection between said cylinders whereby said movable trucks will move in opposite directions to accommodate themselves to irregularities in the supporting surface, means for interrupting said connection to prevent the movement of said pistons, and devices carried by said pistons for positively locking the same against movement.

20. In an excavatin machine, the combination, with a platform to support the excavating devices, of a plurality of trucks for supporting said platform, two Huidcontaining cylinders secured to said platform near one end thereof and on opposite sides of the center thereof, pistons mounted in saidc linders, two of said trucks being connected7 respectively with said pistons, a connection between said cylinders whereby said movable trucks will move in opposite directions to accommodate themselves to irregularities in the supporting surface, and two separate means for preventing the movement of said pistons in said cylinders, whereby either of said means may be utilized to retain said trucks in their adjusted positions.

21. In an excavating machine, the combination, with a supporting platform to carry the excavating devices, of a plurality of trucks to support said platform, two of said trucks being connected with said platform on opposite sides of the center thereof and being capable of vertical movement relatively one to the other and to said platform, a connection between said vertically movable trucks to cause both of them to move relatively to said platform when one of them encounters an irregularity in the supporting surface, means to lock said trucks in adjusted positions, and means to adjust both trucks in the same direction either toward or away from said platform to vary the distance between the platform and the supporting surface.

22. In an excavating machine, the combination, with a supporting platform to carry the excavating devices, of a plurality of trucks to support said platform, cylinders secured to said platform near one end thereof and on opposite sides of the center thereof, said cylinders containinganon-com ressible fluid, pistons mounted in said cylin ers, two of said supporting trucks being arranged tIl() vmecum beneath the respective cylinders and connected with the pistons of said cylinders, means for connecting said cylinders one with the other to permit said trucks to rise and fall to adjust themselves to irregularities in the supporting surface, and means to control the amount of fluid in said cylinder to regulate the distance between the trucks and the platform.

23. In an excavating machine, the combination, with a supporting platform to carry the excavating devices, of a plurality of trucks to support said platform, cylinders secured to said platform near one end thereof and on opposite sides of the center thereof, said cylinders containing a noncompressible fluid, pistons mounted in said cylinders, two of said supporting trucks being arranged beneath the respective cylin.

ders and connected with the istons of said cylinders, means for connecting said cylindears one with the other to permit said trucks to rise and fall to adjust themselves to irregularities in the supporting surface, a receptacle connected with said cylinders, and means to transfer fluid from said receptacle to said cylinders or from said cylinders to said receptacle, thereby varying the distance between the trucks and the platform.

24. In an excavating machine, the combination, with a supporting platform to carry the excavating devices, of a plurality of trucks to support said platform, cylinders secured to said platform near one end thereof and on opposite sides of the center thereof, said cylinders containing a noncompressible fluid, pistons mounted in said cylinders, two of said supporting trucks being arranged beneath the respective cylinders and connected with the pistons of said cylinders, means for connecting said cylinders one with the other to permit said trucks td rise and fall to adjust themselves to irregularities in the supporting surface, a fluid-containing receptacle connected with said cylinders, means to control the communication between said cylinders and said receptacle, and a pump to force the fluid from said receptacle into said cylinders, thereby causing the pistons to work at a greater or lesser distance from the ends of the cylinders and vary the distance between the trucks and the platform.

25. In an excavating machine, the combination, with a supporting platform to carry the excavating devices, off a plurality of trucks to support said platform, cylinders secured to said platform near one end thereof and on opposite sides of the center thereof, said cylinders containing a noncompressible fluid, pistons mounted in said cylinders, two of said supporting trucks being arranged beneath the respective cylinders and vconnected with the pistons of said cylinders, means for connecting said cylinders one with the other to permit said trucks torise and fall to adjust themselves to irregularities in `the supporting surface, means to control the amount of fluid in said cylinder to regulate the distance between the trucks and the platform, and means to lock said trucks in their adjusted positions relatively to said platfrom.

26. In an excavating machine, the combination, with a supporting platform to carry the excavating devices, of a plurality of trucks to support said platform, cylinders secured to said platform near one end thereof and on opposite sides of the center thereof, said cylinders containing a noncompressible fluid, pistons mounted in said cylinders, two of said supporting trucks being arranged beneath the respective cylinders and connected with the pistons of said cylinders, means for connecting said cylinders one with the other to permit said trucks to rise and fall to adjust themselves to irregularities in the supporting surface, means to control the amount of fluid in said cylinders to regulate the distance between the trucks and the platform, and means to lock said trucks both in their adjusted positions relatively one to the other and in their adjusted positions relatively with said platform.

In testimony whereof we affix our signatures in the presence of Witnesses.

CHARLES B. KING. GRANT HOLMES. BENJAMIN J ACGBY. HERBERT E. ROUSH.

Witnesses to the signatures of Charles B. King, Benjamin Jacoby, and Herbert E. Roush:

D. L. CULP, WM. (ir. SLICK.

Witnesses to the signature of Grant Holmes:

VALTER C. LINDLEY,

GER'rnUDn C. KOCH. 

